Biodiversity refers to the menagerie of life on Earth, including genetic diversity, species diversity, and ecosystem diversity. Genetic diversity is the variability of genes within a species. Species diversity is the diversity and richness of different species living in a given community. Ecosystem diversity is the variations in ecosystems within a geographical location and the large number of natural communities and ecosystems around the world.

From the perspective of humans, biodiversity guarantees our food source. Almost all of our food comes from animals and plants, but 90% of the world's food comprises 15 species of plants, and only about 150 species, most of which are now cultivated, are used for food. As wild varieties of these plants have genetic variability and natural disease resistance, cross-breeding between domesticated crops and their wild relatives can often improve disease resistance. Therefore, the loss of wild plants equals the loss of important genetic diversity, which in return causes a sharp decline in our food supply.

Biodiversity plays an important role in our health. When we get sick, we rely on mother nature to recover. For years, people have been seeking a cure for injuries and diseases in the natural world. Plants contain effective ingredients for synthesizing into modern medicine, e.g. the ingredients for aspirin. Homeopathic medicine also makes great use of botanical ingredients. From a value standpoint, plants that are used for medicine have a value above estimation. The total value of these plant-based drugs in the world is about RMB 600 billion. If we continue to destroy biodiversity, species, and habitats, we will forever lose those ingredients that are conducive for our health.

We must breathe to live. But living in cities, car exhaust, factory emissions, air pollution from power plants, and more make the air we breathe very unhealthy. We call for green cities and garden cities, indicating that biodiversity is vital to our environment and the air purification.

Biodiversity also has a close relationship with water resources. Clean water is vital to human life. Only when healthy biodiversity is ensured can we have the healthy water resources.

Biodiversity is the provider of raw materials for building our homes. We build houses and make furniture out of trees and wood. Trees as well as other plants are widely used in paper production, having become an indispensable part in our daily lives.

Biodiversity guarantees the quality of human life. People cherish nature and are attracted to its beauty. Magical landscapes with gorgeous creatures show the beauty of nature, which brings joy to our lives and enriches our experience of it. Majestic and beautiful mountains and rivers with colorful flowers, birds, fish, and insects, culminating in a pleasing view. The gift of nature improves our lives. Losing biodiversity means we and the following generations won’t be able to appreciate the beauty and wonder of nature ever again.

In addition, biodiversity is extremely crucial to the world economy. A healthy environment lays the foundation for healthy economy and stable society. Without products and services provided by diverse natural systems, we would not be able to survive, let alone thrive.

The inherent value of biodiversity far outweighs its value to humans. Animals and plants live with us on this planet. For considering them alone, biodiversity is worth preserving. Many nations and cultures believe that the Earth can be relied upon and is the basis of their religion or belief system.

(2) Loss of biodiversity

We are rapidly losing biodiversity as a result of explosions in the human population and over-consumption of natural resources. The main factors that lead to biodiversity loss are:

Degradation and loss of habitats: The greatest and only threat to biodiversity is that land development and agricultural production damage natural flora and fauna. Development activities aggravate air and water pollution as well, then speed up environment degradation and further reduce biodiversity; new developments and construction exacerbate soil erosion of land without vegetation, and soil erosion accelerates sedimentation, leading to a reduction in the capacity of streams to recycle nutrients and organic waste.

Invasive and alien species: Invasive and alien species change natural ecosystems; non-native flora and fauna may encroach on large available habitats of native species in order to obtain resources; other alien species can prey upon native species and will have no natural predators to keep them in check. For those invasive species, some were deliberately introduced by humans, while others entered accidentally through international trade.

Global climate change: Vehicles and industrial production emit carbon dioxide which accumulates greenhouse gases in the atmosphere; rising temperatures coupled with increased UV radiation lead to habitat changes, affecting the lives of plants and animals; climate warming causes changes in animal migration patterns and the inconsistence of the blossoming of flowering plants and the pace of the birds they rely on for pollination.

Overpopulation and over-consumption of resources: The global population has already exceeded 6 billion and is still growing rapidly; more and more people are in need of fresh water and fuel, putting a heavy burden on our global and local ecosystems and intensifying the demand of people around the world for material goods and services; however, the per capita resource consumption of industrialized countries is much higher than that of developing countries.

Exploitation and utilization of wildlife: wildlife trade, poaching, hunting for food, and traditional medicine are unsustainable and have resulted in significant loss of biodiversity; overfishing of local fisheries has brought some aquatic species to the brink of extinction and reduced the overall diversity of aquatic species.

(3) Biodiversity in China

China has rich biodiversity and is the home of more than 30,000 species of higher plants. Among the 850 species of 15 families of gymnosperms in the world, 10 families and about 250 species are in China, crowning it the country with the largest number of gymnosperms in the world. There are 6,347 species of vertebrates in China, accounting for nearly 14% of the world's total species. China is the native home of rice and soybeans, with 50,000 and 20,000 varieties, respectively. Endemic genera and species are redundant in China, especially endemic species of higher plants, which total about 17,300 species, accounting for more than 57% of the total number of higher plants in China. Among the 6,347 species of vertebrates, 667 are endemic species, accounting for 10.5% of the total number of vertebrates. China is a country with vast territory, complex and diverse geographical environments, and significant climate difference in the north and south. As a result, China's ecosystem is rich and diversified, nearly including all the different types of habitats found on Earth.

China has the highest population in the world. The excessively and rapidly growing population has caused large losses to and fragmentation of animal and plant habitats and brought enormous pressure on natural resources. Industrial development and rapid economic growth have caused serious air and water pollution, which have further deteriorated the living environment of animals and plants. Excessive wildlife hunting, reclamation of mountains and land, degradation and desertification of grasslands and pastures caused by overgrazing, deforestation, soil and water erosion, and other human activities have resulted in the loss in both species diversity and ecosystem diversity. Introduced invasive species have brought many native species to extinction. According to the statistics of the Ministry of Agriculture, at present, there are 380 alien plants and 40 alien animals in China, causing the direct or indirect economic losses up to RMB 119.876 billion. In order to conserve China's biodiversity, the Chinese government has implemented various methods. It enacted a series of laws and regulations and acceded to the Convention on Biological Diversity; established 1,227 nature reserves nationwide, covering a total area of ​​9,821 hectares, accounting for 9.85% of national land area; completely halted the logging of natural forests in many provinces and cities, and implemented the grain for green project.

(4) What can we do to protect biodiversity?

Recently, governments have gradually recognized the significance of biodiversity and its conservation and have promulgated and improved related laws and regulations. As ordinary citizens, we can also take various actions to conserve biodiversity every day. For example:

· Oppose deforestation and poaching;

· Refuse to consume wild animals and plants;

· Eat foods from native species as well as vegetables and fruits currently in season;

· Support organic products;

· Resist the fur trade and products made from endangered animals or their body parts (e.g., ivory, sea turtle shells, musk, etc.). If you discover any of these products, please report it to the relevant departments, the police, or the media in a timely manner;

· Refuse to use medicines made from wildlife;

· Choose domestic animals rather than wild animals as pets;

· Conserve wildlife habitats;

· Learn more about biodiversity and share it with your family and friends;

· Drive less; utilize public transport, cycle, or walk more often; and encourage others to do the same;

· Use rechargeable batteries and recycle non-rechargeable batteries;

· Reuse and recycle any item whenever possible, and reduce new purchases;